The Dreyfuss caliber 39 is actually an Eterna caliber 39. This movement is modular and Dreyfuss chose to use it as a manual wind movement in their pilot style flieger watch here. This takes it from the typical 29 jewels in the Eterna automatic version to 20 jewels in the Dreyfuss version.
For years, Eterna has focused its efforts on enlarging both its manufacturing technologies as well as its movement portfolio. Thanks to the modularity of the Calibre 39, the same base movement can give rise to a total of 88 different movement versions. This, once again, is a testament to Eterna‘s ability to further refine past achievements in the development of watch movements with its inventiveness and precision work.